It comes at a time when the average mortgage nationally is $488,875 and, in the overheated Sydney market, the average home loan has now passed a whopping $600,000, according to major mortgage broker AFG.

Adding to the gloomy picture, the Housing Industry Association (HIA) says it now takes more than two average full-time wages to affordably service the loan for a typical Sydney home.

According to the HIA, Sydneysiders must fork out $4,729 per month, or $57,000 a year, for an average priced dwelling.

Here's the rub.

If the Reserve Bank is looking to raise interest rates, your mortgage is going to go up.

If you are one of the up to 800,000 people already struggling to pay your bills, things are going to get harder.

Given the signals from the Reserve Bank, then it's reasonable to expect that if the economy keeps improving interest rates will at some point rise by 2 percentage points to that neutral rate of 3.5 per cent.

If you have the average home loan of $489,000, that's an extra $815 a month.

If you live in Sydney, with the average Sydney loan of $600,000, that will be $1,000 a month.